TWI798311B - Epoxy resin composition and cured product thereof - Google Patents

Abstract

An object of the present invention is to provide a composition for epoxy resin which exhibits excellent heat resistance, flame retardancy, low hygroscopicity, and adhesiveness, and in particular, gives excellent cured product properties in printed wiring board applications.

An epoxy resin composition according to the present invention comprises an epoxy resin and a curing agent as essential components, wherein at least a part of the curing agent is a biphenylaralkyl type phenol resin represented by the following general formula (1), and in the biphenylaralkyl type phenol resin, the component in which n is 0 in the general formula (1) is less than 15 area% and the component in which n is 5 or more is 20 area% or more according to gel permeation chromatography measurement.

Description

Epoxy resin composition and its hardened product

The present invention relates to an epoxy resin composition excellent in high heat resistance, low moisture absorption, flame retardancy, adhesiveness, etc., its cured product, prepreg, laminate, and printed circuit board.

Epoxy resin compositions can be used in various fields such as coatings, civil engineering bonding, casting, electrical and electronic materials, and film materials due to their excellent adhesiveness, flexibility, heat resistance, chemical resistance, insulation, and curing reactivity. In particular, in the use of printed wiring boards, which are one of electrical and electronic materials, imparting flame retardancy to epoxy resin compositions is widely practiced.

In recent years, with the rapid development of miniaturization and high performance of information devices, materials used in the field of semiconductors and electronic parts are required to have higher performance than at present. In particular, epoxy resin compositions are required to have high heat resistance with a glass transition temperature of 150° C. or higher and low moisture absorption from the viewpoint of reliability.

As shown in Patent Document 1, amine-based hardeners such as dicyandiamine (DICY) have been used to increase the heat resistance of laminates. However, when this hardener is used as a wiring board, the hygroscopicity of the board may increase. question.

Therefore, a highly heat-resistant hardener derived from a phenolic structure has been developed. With regard to the phenol hardener as a high heat-resistant hardener, for example, Patent Document 2 discloses the use of a naphthol resin as an epoxy resin When using a resin hardener, heat resistance is improved compared to general phenolic novolac resins. However, flame retardancy cannot be fully satisfied. In particular, when used as a laminate, the adhesiveness to substrates such as glass cloth is low, and interfacial peeling tends to occur when used as a laminate.

Also, in Patent Document 3, a naphthol novolak-type resin is used as a curing agent for epoxy resins, but it is easily decomposed under high heat conditions, and cannot exhibit sufficient heat resistance and flame retardancy.

Patent Document 4 discloses that using a triphenylmethane type phenolic resin as a curing agent achieves improved workability and high heat resistance by lowering the viscosity, but is poor in flame retardancy.

Patent Documents 5 and 6 disclose the use of a biphenol-biphenyl aralkyl type resin as a raw material phenol resin for an epoxy resin, but do not teach the use as a curing agent. Patent Document 7 discloses the use of a polyhydric hydroxy compound obtained from 4,4-biphenol and bis(dimethylol)biphenyl as a curing agent as a comparative example. However, the heat resistance of the disclosed polyhydric hydroxyl compounds is not sufficient.

Epoxy resin compositions using conventional phenolic hardeners cannot fully meet the performance requirements for high functionality in recent years, and are insufficient to ensure adhesion while maintaining sufficient heat resistance and flame retardancy.

[Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Unexamined Patent Publication No. 2006-36798

[Patent Document 2] Japanese Unexamined Patent Publication No. 2007-31527

[Patent Document 3] Japanese Patent Application Laid-Open No. 7-215902

[Patent Document 4] Japanese Patent Application Laid-Open No. 11-49846

[Patent Document 5] WO2011/074517

[Patent Document 6] Japanese Patent Laid-Open No. 2017-095524

[Patent Document 7] Japanese Patent Laid-Open No. 2006-248912

The problem to be solved by the present invention is to provide an epoxy resin composition that exhibits excellent heat resistance, flame retardancy, low moisture absorption and adhesiveness in the cured product, and especially imparts excellent cured product characteristics for printed circuit board applications .

In order to solve the above-mentioned problems, the inventors of the present invention conducted intensive studies on phenol resins, and as a result, found that a biphenylaralkyl-type phenol obtained by reacting a biphenol compound with a biphenyl-based condensing agent and having a ratio of constituent components within a specific range was used. When the resin is used as a phenolic curing agent, the resulting cured product has excellent heat resistance, flame retardancy, low moisture absorption and adhesiveness, thus completing the present invention.

That is, the present invention is an epoxy resin composition, which contains an epoxy resin and a curing agent as essential components, wherein at least a part of the above curing agent is a biphenyl aralkyl group represented by the following general formula (1) Type phenol resin, this biphenyl aralkyl type phenol resin is measured in gel permeation chromatography, and the component that n is 0 in general formula (1) does not reach 15 area %, and n is 20 area % of the component of 5 or more above,

(Here, n is the number of repeating units and represents a number of 0 or more, and its average value is a number of 1.3 to 20, and R ¹ , R ² and R ³ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 8 carbons).

A part or all of the above-mentioned epoxy resins are preferably phosphorus-containing epoxy resins.

Also, the present invention is a cured product obtained by curing the above-mentioned epoxy resin composition. Also, the present invention is a prepreg, a laminate, or a printed wiring board characterized by using the above-mentioned epoxy resin composition.

And, the present invention is a kind of biphenyl aralkyl type phenol resin, is the biphenyl aralkyl type phenol resin shown in above-mentioned general formula (1), this biphenyl aralkyl type phenol resin is in gel permeation In the chromatographic measurement, the component where n is 0 in the general formula (1) is less than 15 area %, and the component where n is 5 or more is 20 area % or more.

The epoxy resin composition of the present invention can be used for printed circuit boards because it exhibits excellent heat resistance, flame retardancy, low moisture absorption, and adhesiveness in its cured product. In particular, it can be used as a substrate for vehicles requiring high reliability.

Fig. 1 is a GPC chart of the biphenyl aralkyl type phenol resin obtained in Synthesis Example 1.

Figure 2 is a GPC chart of the biphenyl aralkyl type phenol resin obtained in Synthesis Example 2.

Fig. 3 is a GPC chart of the biphenyl aralkyl type phenol resin obtained in Synthesis Example 3.

Figure 4 is a GPC chart of the biphenyl aralkyl type phenol resin obtained in Synthesis Example 4.

Fig. 5 is a GPC chart of the biphenyl aralkyl type phenol resin obtained in Synthesis Example 5.

Fig. 6 is a GPC chart of the biphenyl aralkyl type phenol resin obtained in Synthesis Example 6.

Fig. 7 is a GPC chart of the biphenyl aralkyl type phenol resin obtained in Synthesis Example 7.

Embodiments of the present invention will be described in detail below.

The epoxy resin composition of the present invention uses epoxy resin and hardener as essential components. At least a part of the curing agent is a biphenyl aralkyl type phenol resin represented by the above general formula (1).

In the general formula (1), R ¹ , R ² , and R ³ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 8 carbons. Examples of hydrocarbon groups having 1 to 8 carbons include alkyl groups having 1 to 8 carbons such as methyl, ethyl, propyl, isopropyl, n-butyl, tert-butyl, and hexyl, and alkyls having 5 carbons such as cyclohexyl. Cycloalkyl to 8, aryl with 6 to 8 carbons such as phenyl, tolyl, and xylyl, aralkyl with 7 to 8 carbons such as benzyl, phenethyl, and 1-phenylethyl , but not limited to these, each may be the same or different. Desirable R ¹ , R ² , and R ³ are hydrogen atoms, 1-phenylethyl groups, or methyl groups from the viewpoint of ease of acquisition and physical properties such as heat resistance when forming a cured product.

n is the number of repeating units and represents a number of 0 or more, and its average value (number average) is 1.3 to 20, preferably 1.5 to 15, more preferably 1.7 to 10, and still more preferably 2 to 6.

The average value of n can be obtained by calculating from the phenolic hydroxyl equivalent of the biphenyl aralkyl type phenol resin if the structure of the above formula (1) can be identified. For example, in the case of Synthesis Example 1, a biphenylaralkyl type phenol resin represented by the following formula (2) can be obtained. The molecular weight was calculated as (186+364×n'), and the number of phenolic hydroxyl groups in one molecule was determined as (2+2×n'). Since the phenolic hydroxyl equivalent is 158g/eq., the following calculation formula 158=(186+364×n')/(2+2×n') is established, and n' is obtained as 2.7.

Also, the weight average molecular weight (Mw) measured by GPC is preferably 1,000 to 8,000, more preferably 2,000 to 7,000, and still more preferably 3,000 to 6,000.

From the viewpoint of solvent solubility, when n is 0, that is, the content of n=0 components is less than 15 area % in GPC measurement, preferably 10 area % or less, more preferably 6 area % or less. In particular, when used in a laminated board application and the like by dissolving in an organic solvent, it is preferably 2 to 5 area %.

From the viewpoint of improving heat resistance, the content of n=5 or more components is 20 area % or more, preferably 25 area % or more, more preferably 27 area % or more. In addition, the measurement conditions of GPC were based on the method described in the Example.

The phenolic hydroxyl equivalent is preferably 140 to 180 g/eq., more preferably 145 to 170 g/eq., and still more preferably 150 to 160 g/eq. The softening point is preferably from 100 to 160°C, more preferably from 110 to 150°C, and still more preferably from 120 to 140°C.

The said biphenyl aralkyl type phenol resin can be manufactured by the method disclosed by patent document 5 etc. Specifically, in this method, 1 mol of a biphenol compound and less than 1 mol of a biphenyl-based condensing agent are reacted with respect to a biphenol compound and a biphenyl-based condensing agent.

Examples of the above-mentioned biphenol compound include 4,4'-biphenol, 2,4'-biphenol, or 2,2'-biphenol, etc., and 4,4'-biphenol is preferred from the viewpoint of reactivity. phenol. In addition, these biphenol compounds may have one hydrocarbon group having 1 to 8 carbon atoms as a substituent on each aromatic ring.

Examples of the biphenyl-based condensing agent include: biphenyl-4,4'-dimethanol, 4,4'-bis(chloromethyl)biphenyl, 4,4'-bis(bromomethyl)biphenyl, 4,4'-bis(methoxymethyl)biphenyl, 4,4'-bis(ethoxymethyl)biphenyl, biphenyl-2,4'-dimethanol, 2,4'-bis (Chloromethyl)biphenyl, 2,4'-bis(bromomethyl)biphenyl, 2,4'-bis(methoxymethyl)biphenyl, 2,4'-bis(ethoxymethyl) ) biphenyl, biphenyl-2,2'-dimethanol, 2,2'-bis(chloromethyl)biphenyl, 2,2'-bis(bromomethyl)biphenyl, 2,2'-bis (Methoxymethyl)biphenyl, 2,2'-bis(ethoxymethyl)biphenyl, etc. From the viewpoint of reactivity, biphenyl-4,4'-dimethanol and 4,4'-bis(chloromethyl)biphenyl are preferable, and from the viewpoint of reduction of ionic impurities, biphenyl Biphenyl-4,4'-dimethanol, 4,4'-bis(methoxymethyl)biphenyl. In addition, these biphenyl-based condensing agents may have one or two hydrocarbon groups having 1 to 8 carbon atoms as substituents on each aromatic ring.

In the reaction between the biphenol compound and the biphenyl-based condensing agent, an excessive amount of the biphenol compound is used with respect to the biphenyl-based condensing agent. The amount of the biphenyl-based condensing agent used is preferably 0.1 to 0.55 mol, more preferably 0.3 to 0.5 mol, relative to 1 mol of the biphenol compound. If the amount of biphenyl-based condensing agent used is too large, the formation of n=0 components will decrease, but the molecular weight itself will increase, and the softening point and melt viscosity of the resin will increase, which may hinder moldability or workability. On the other hand, when it is too small, the amount other than the excess biphenol compound after completion|finish of reaction will increase, and it is unfavorable industrially.

Usually, this reaction is carried out in the presence of known acid catalysts such as inorganic acids and organic acids. Examples of such acid catalysts include inorganic acids such as hydrochloric acid, sulfuric acid, and phosphoric acid, organic acids such as formic acid, oxalic acid, trifluoroacetic acid, and p-toluenesulfonic acid, zinc chloride, aluminum chloride, ferric chloride, and boron trifluoride. Such as Lewis acid, or solid acid such as activated clay, silica-alumina, zeolite, etc.

Usually the reaction is carried out at 10 to 250°C for 1 to 20 hours. In addition, during the reaction, the solvent is preferably used for example: alcohols such as methanol, ethanol, propanol, butanol, ethylene glycol, methyl cellosulo, ethyl cellosulo, diethylene glycol dimethyl ether, Ethers such as triethylene glycol dimethyl ether (triglyme), or halogenated aromatic compounds such as chlorobenzene and dichlorobenzene, etc. Among them, ethyl cellophane, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether are particularly preferred. Ethylene glycol dimethyl ether, etc.

The biphenyl aralkyl type phenolic resin obtained by the above method sometimes contains more than 15% by area of n=0 components, so it is preferable to perform a step of removing n=0 components if necessary after the reaction is completed. From the viewpoint of solvent solubility, the content of n=0 component is less than 15 area %, preferably 10 area % or less, more preferably 6 area % or less, most preferably 3 to 5 area %.

In the step of removing the n=0 component of the biphenyl aralkyl type phenol resin, for example, in order not to dissolve the n=0 component but to dissolve the high molecular weight component with n=1 or more, it is preferable to use a poor mixing solvent Solvent with good solvent, remove n=0 components by filtration or other methods. The poor solvent is not particularly limited as long as it hardly dissolves the n=0 component, and examples thereof include aromatic solvents such as benzene, toluene, and xylene. Good solvents include the aforementioned alcohols, ethers, halogenated aromatic compounds, or ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.

The softening point of the biphenyl aralkyl type phenolic resin can be easily adjusted by changing the molar ratio between the biphenol compound and the biphenyl-based condensing agent which are the raw materials of the resin, but it can be changed by reducing the high molecular weight component When the molar ratio of the biphenol compound and the biphenyl-based condensing agent increases, the content of the n=0 component that must be removed increases, which deteriorates the workability and greatly reduces the yield, so there is a limit.

The epoxy resin composition of the present invention uses the above-mentioned biphenyl aralkyl type phenol resin and epoxy resin as essential components.

唑啶酮環的環氧樹脂、或後述的反應性稀釋劑等，但並不限定於該等。又，該等環氧樹脂可單獨使用，亦可併用2種類以上。積層板用途而言，較佳係使用萘二酚型環氧樹脂、酚酚醛清漆型環氧樹脂、苯乙烯化酚酚醛清漆型環氧樹脂、甲酚酚醛清漆型環氧樹脂、α-萘酚芳烷基型環氧樹脂、二環戊二烯型環氧樹脂、含磷的環氧樹脂、含

唑啶酮環的環氧樹脂。 The epoxy resin can be used for the epoxy resin which has 2 or more epoxy groups in a molecule|numerator. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, tetramethylbisphenol F type epoxy resin, hydroquinone type epoxy resin, biphenyl type epoxy resin, bisphenol Spike type epoxy resin, bisphenol S type epoxy resin, disulfide type epoxy resin, resorcinol type epoxy resin, biphenyl aralkylphenol type epoxy resin, naphthalene diol type epoxy resin , Phenol Novolac Epoxy Resin, Styrenated Phenol Novolac Epoxy Resin, Cresol Novolac Epoxy Resin, Alkyl Novolac Epoxy Resin, Bisphenol Novolac Epoxy Resin, Naphthol Novolak Epoxy Resin Varnish type epoxy resin, β-naphthol aralkyl type epoxy resin, dinaphthol aralkyl type epoxy resin, α-naphthol aralkyl type epoxy resin, paraphenylmethane type epoxy resin, Paraphenylmethane type epoxy resin, dicyclopentadiene type epoxy resin, alkanediol type epoxy resin, aliphatic cyclic epoxy resin, diaminodiphenylmethane tetraglycidylamine, amine group Phenolic epoxy resins, phosphorus-containing epoxy resins, urethane-modified epoxy resins,

An epoxy resin with an oxazolidone ring, or a reactive diluent described later, etc., are not limited thereto. Moreover, these epoxy resins may be used individually, and may use 2 or more types together. For laminate applications, it is preferable to use naphthalene diol type epoxy resin, phenol novolak type epoxy resin, styrenated phenol novolak type epoxy resin, cresol novolak type epoxy resin, α-naphthol Aralkyl type epoxy resin, dicyclopentadiene type epoxy resin, phosphorus-containing epoxy resin,

Epoxy resins with pyroxazidone rings.

An epoxy resin obtained by epoxidizing the phenolic hydroxyl group of the biphenyl aralkyl type phenol resin represented by the above general formula (1) as a raw material can also be used.

The epoxy equivalent (g/eq.) of these epoxy resins is preferably 100-800, more preferably 200-780, more preferably 300-760, particularly preferably 400-740.

In the field where flame retardancy is required, it is preferable to use alone or two or more kinds of phosphorus-containing epoxy resins, and it is also possible to use phosphorus-free epoxy resins in combination. Phosphorous epoxy resin, As disclosed in Japanese Patent Application Publication No. 04-11662, Japanese Patent Application Publication No. 05-214070, Japanese Patent Application Publication No. 2000-309624, and Japanese Patent Application Publication No. 2002-265562, the Tejia system uses 9, 10-2 Reaction of reactive phosphorus compounds such as hydrogen-9-oxa-10-phosphaphenanthrene-10-oxide or diphenylphosphine oxide with optional quinone compounds such as 1,4-benzoquinone or 1,4-naphthoquinone After that, it is obtained by reacting with epoxy resin. The phosphorus content of these phosphorus-containing epoxy resins is preferably from 0.5 to 7% by mass, more preferably from 1 to 6% by mass, still more preferably from 2 to 5.5% by mass, particularly preferably from 3 to 5% by mass.

Also, the phosphorus-free epoxy resin that can be used in combination is not particularly limited, and the above-mentioned epoxy resins can be used in combination, but a trifunctional or higher functional epoxy resin such as a novolac epoxy resin is preferable. When a phosphorus-free epoxy resin is used in combination, the phosphorus content of the mixed epoxy resin composition of the phosphorus-containing epoxy resin and the phosphorus-free epoxy resin is better than that of the phosphorus-containing epoxy resin. As for the phosphorus content, the phosphorus content of the phosphorus-containing epoxy resin or the mixing amount of the phosphorus-containing epoxy resin and the phosphorus-free epoxy resin is adjusted.

Specific examples of phosphorus-containing epoxy resins include, for example: Epotohto FX-305, Epototo FX-289B, Epototo FX-1225, YDFR-1320, TX-1328 (the above are manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd.), etc. But not limited to these.

In addition to the above-mentioned biphenyl aralkyl type phenolic resins, one or more types of phenolic resins, acid anhydrides, amines, hydrazines, acidic polyesters, and other commonly used hardeners can also be used in combination if necessary. Hardener for epoxy resin. When these curing agents are used in combination, the amount of the curing agent used in combination is preferably 70% by mass or less, more preferably 50% by mass or less in the total curing agent. When the ratio of the curing agent used in combination is too large, there is a possibility that the heat resistance and flame retardancy of the epoxy resin composition will deteriorate.

In the epoxy resin composition, relative to 1 mole of epoxy groups in the full epoxy resin, the amount of hardener used is preferably in the range of 0.2 to 1.5 mole of active hydrogen groups in the hardener, more preferably It is 0.3 to 1.4 mol, more preferably 0.5 to 1.3 mol, most preferably 0.8 to 1.2 mol. When it is out of this range, hardening will become incomplete, and there exists a possibility that favorable hardening physical property may not be acquired. For example, when using a phenol-based hardener or an amine-based hardener, an active hydrogen group of about equimolar relative to the epoxy group is prepared; 0.5 to 1.2 moles of acid anhydride groups are prepared, preferably 0.6 to 1.0 moles of acid anhydride groups are prepared. When the above-mentioned phenolic resin is used alone, it is preferable to use 0.9 to 1.1 moles of phenolic hydroxyl groups with respect to 1 mole of epoxy groups in the epoxy resin.

The active hydrogen group referred to in the present invention refers to a functional group having an active hydrogen reactive with an epoxy group (including a functional group having a potential active hydrogen that can generate active hydrogen due to hydrolysis, etc., or exhibiting an equivalent hardening effect. functional groups), specifically, acid anhydride groups, carboxyl groups, amino groups, or phenolic hydroxyl groups. In addition, regarding the active hydrogen group, 1 mol of carboxyl group or phenolic hydroxyl group is calculated as 1 mol, and amine group (NH ₂ ) is calculated as 2 mol. Also, when the active hydrogen group is unclear, the active hydrogen equivalent can be obtained by measurement. For example, by reacting a monoepoxy resin such as phenyl glycidyl ether whose epoxy equivalent is known with a hardener whose active hydrogen equivalent is unknown, and measuring the amount of monoepoxy resin eliminated, the used The active hydrogen equivalent of the hardener.

改性酚樹脂(經三聚氰胺、2,4-二胺基-6-苯基-1,3,5-三

(benzoguanamine)等與酚核連結之多官能酚化合物)，萜烯酚樹脂、重油改性酚樹脂等，該等多官能酚化合物經烷基、烷氧基、芳基等取代基進行核取代之多官能酚化合物等，但並不限定該等。 Phenolic resin hardeners that can be used together include: bisphenols, dihydroxybenzenes, hydroxynaphthalene, phosphorus-containing phenolic hardeners, polyfunctional condensation products of phenols such as novolac resins and aldehydes or condensing agents. Phenolic compounds, aminotri

Modified phenolic resin (melamine, 2,4-diamino-6-phenyl-1,3,5-tri

(benzoguanamine) and other multifunctional phenolic compounds linked to phenolic cores), terpene phenolic resins, heavy oil modified phenolic resins, etc., these multifunctional phenolic compounds are nuclear-substituted by substituents such as alkyl, alkoxyl, and aryl groups Polyfunctional phenolic compounds and the like are not limited thereto.

Specific examples of bisphenols include bisphenol A, bisphenol F, bisphenol C, bisphenol K, bisphenol Z, bisphenol S, tetramethylbisphenol A, tetramethylbisphenol F, tetramethylbisphenol Bisphenol S, tetramethylbisphenol Z, dihydroxydiphenyl sulfide, 4,4'-thiobis(3-methyl-6-tert-butylphenol), etc. Specific examples of dihydroxybenzenes include: catechol, resorcinol, methylresorcinol, hydroquinone, monomethylhydroquinone, dimethylhydroquinone, trimethylhydroquinone, mono- tertiary butyl hydroquinone, di-tertiary butyl hydroquinone, etc. Specific examples of hydroxynaphthalene include dihydroxynaphthalene, dihydroxymethylnaphthalene, dihydroxydimethylnaphthalene, and trihydroxynaphthalene. Specific examples of the phosphorus-containing phenol hardener include LC-950PM60 (manufactured by Shin-AT&C), EXB9000A (manufactured by DIC Corporation), and the like.

Polyfunctional phenolic compounds that are condensates of phenols and aldehydes or condensing agents. Specific examples thereof include phenolic novolac resins such as Shonol BRG-555 (manufactured by Aica SDK Phenol Co., Ltd.), DC-5 (Nippon Steel & Sumitomo Metal Co., Ltd. Chemical Co., Ltd.) and other cresol novolak resins, Resitop TPM-100 (Kunei Chemical Industry Co., Ltd.) and other trihydroxyphenylmethane-type novolac resins, naphthol novolak resins, naphthol-phenol co-condensation Novolak resin, naphthol-cresol co-condensation novolac resin, phenol aralkyl resin, or naphthol aralkyl such as SN-160, SN-395, SN-485 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.) resin, dicyclopentadienol resin, biphenyl modified phenol resin, biphenyl modified naphthol resin, etc.

In this case, examples of phenols include phenol, cresol, xylenol, butylphenol, amylphenol, nonylphenol, butylmethylphenol, trimethylphenol, phenylphenol, 1-naphthol, and 2-naphthol. Monophenolic compounds such as phenol, or the above-mentioned bisphenols, dihydroxybenzenes, and hydroxynaphthalenes. Examples of aldehydes include: formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, hexanal, benzaldehyde, chloroacetaldehyde, bromoaldehyde, acetaldehyde, malonaldehyde, succinaldehyde, glutaraldehyde, adipaldehyde , Pimelaldehyde, sebaaldehyde, acrolein, crotonaldehyde, salicylaldehyde, o-phthalaldehyde, hydroxybenzaldehyde, etc. Examples of the condensing agent include: benzenedimethanol, Xylene glycol dimethyl ether, xylylene dihalide, biphenyl-based condensing agent, dimethoxymethylnaphthalene, dichloromethylnaphthalene, divinylbenzene, divinylbiphenyl Divinyl compounds such as dicyclopentadiene, cycloalkyl dienes such as dicyclopentadiene, etc. In addition, examples of the biphenyl-based condensing agent include biphenyl-based condensing agents that can be used as raw materials for the production of the phenol resin used in the present invention.

The acid anhydride hardeners specifically include: methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, pyromelite anhydride, phthalic anhydride, trimellitic anhydride, methyl nadic anhydride (methyl Nadic anhydride) and so on.

Specific examples of amine-based hardeners include: diethylenetriamine, triethylenetetramine, m-xylylenediamine, isophoronediamine, diaminodiphenylmethane, diaminodiphenylsulfone, Condensation of amino diphenyl ether, benzyl dimethylamine, 2,4,6-para(dimethylaminomethyl)phenol, dicyandiamine, dimer acid and other acids with polyamines Amine compounds such as polyamide amine, etc.

Other curing agents specifically include: phosphine compounds such as triphenylphosphine, phosphonium salts such as tetraphenylphosphonium bromide, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2 -Imidazoles such as undecylimidazole, 1-cyanoethyl-2-methylimidazole, imidazole salts of imidazoles, trimellitic acid, isocyanuric acid, boron, etc., trimethylammonium Chloride and other quaternary ammonium salts, diazabicyclic compounds, salts of diazabicyclic compounds and phenols, phenol novolac resins, etc., boron trifluoride and amines, ether compounds, etc. family phosphonium, or iodonium salt, etc.

The epoxy resin composition may use a hardening accelerator as needed. Examples of usable hardening accelerators include imidazoles such as 2-methylimidazole, 2-ethylimidazole, and 2-ethyl-4-methylimidazole, 2-(dimethylaminomethyl)phenol, Tertiary amines such as 1,8-diaza-bicyclo(5,4,0)undec-7-ene, and phosphines such as triphenylphosphine, tricyclohexylphosphine, and triphenylphosphinetriphenylborane Classes, metal compounds such as tin octoate, etc. Relative to 100 parts by mass of the epoxy resin component in the epoxy resin composition of the present invention, preferably A hardening accelerator is used in an amount of 0.02 to 5 parts by mass. By using a hardening accelerator, the hardening temperature can be lowered or the hardening time can be shortened.

Organic solvents or reactive diluents can be used to adjust the viscosity of the epoxy resin composition.

Examples of organic solvents include amides such as N,N-dimethylformamide and N,N-dimethylacetamide, ethylene glycol monomethyl ether, dimethoxydiethylene glycol, ethylene glycol, Glycol diethyl ether, diethylene glycol diethyl ether, triethylene glycol dimethyl ether and other ethers, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and other ketones, Methanol, ethanol, 1-methoxy-2-propanol, 2-ethyl-1-hexanol, benzyl alcohol, ethylene glycol, propylene glycol, butylene glycol, pine oil and other alcohols, Butyl Acetate, Methoxybutyl Acetate, Methyl Cellosuloacetate, Cellosuloacetate, Ethyl Diethylene Glycol Acetate, Propylene Glycol Monomethyl Ether Acetate, Carbitol B Acetate esters such as esters and benzyl alcohol acetate, benzoate esters such as methyl benzoate and ethyl benzoate, cellosuloids such as methyl cellosul, cellosul, and butyl cellosul , methyl carbitol, carbitol, butyl carbitol and other carbitols, benzene, toluene, xylene and other aromatic hydrocarbons, dimethyl sulfoxide, acetonitrile, N-methylpyrrolidone, etc., but is not limited to such.

Examples of reactive diluents include monofunctional glycidyl ethers such as allyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, and triglycidyl ether. Base ethers, resorcinol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, Difunctional glycidyl ethers such as cyclohexanedimethanol diglycidyl ether, propylene glycol diglycidyl ether, glycerin polyglycidyl ether, trimethylolpropane polyglycidyl ether, trimethylolethane Multi-functional glycidyl ethers such as polyglycidyl ether and neopentylthritol polyglycidyl ether, new Glycidyl esters such as capric acid glycidyl ester, glycidyl amines such as phenyl diglycidyl amine and cresyl diglycidyl amine, but not limited to these.

It is preferable to use 20 to 90% by mass of the organic solvent as a non-volatile component, which is a mixture of single or plural types, and the appropriate type or usage amount is appropriately selected according to the application. For example, in the application of printed circuit boards, polar solvents such as methyl ethyl ketone, acetone, and 1-methoxy-2-propanol with a boiling point below 160°C are preferred, and the amount used is preferably 40% in terms of non-volatile matter. to 80% by mass. Also, in the application of adhesive films, it is preferable to use, for example, ketones, acetates, carbitols, aromatic hydrocarbons, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc. , its usage is preferably 30 to 60% by mass in terms of non-volatile matter.

Reactive diluents are mainly solvent-free, and are used to reduce viscosity or adjust gel time. If the amount is too high, the hardening reaction may not proceed sufficiently, causing unreacted components to ooze out of the hardened product or reduce the physical properties of the hardened product such as mechanical strength, so it is better not to use excessively. Therefore, in the epoxy resin, it is preferably at most 30% by mass, more preferably at most 20% by mass, and even more preferably at most 10% by mass.

The epoxy resin composition can be blended with other thermosetting resins and thermoplastic resins within the range that does not impair the properties. Examples include phenol resins, acrylic resins, petroleum resins, indene resins, coumarone-indene resins, phenoxy resins, polyurethane resins, polyester resins, polyamide resins, Polyimide resin, polyamideimide resin, polyetherimide resin, polyphenylene ether resin, modified polyphenylene ether resin, polyether resin, polyether resin, polyether ether ketone resin, Polyphenylene sulfide resin, polyvinyl formaldehyde resin, etc., but not limited to these.

Various known flame retardants can be used in the epoxy resin composition for the purpose of improving the flame retardancy of the obtained cured product. The flame retardants that can be used include, for example: halogen flame retardants, phosphorus flame retardants, nitrogen flame retardants, polysiloxane flame retardants, inorganic flame retardants, organic metal salt flame retardants, etc. . From the viewpoint of environmental friendliness, a halogen-free flame retardant is preferred, and a phosphorus-based flame retardant is particularly preferred. These flame retardants can be used individually or in combination of 2 or more types.

As the phosphorus-based flame retardant, any of inorganic phosphorus-based compounds and organic phosphorus-based compounds can be used. Examples of inorganic phosphorus-based compounds include red phosphorus, ammonium phosphates such as monoammonium phosphate, diammonium phosphate, triammonium phosphate, and ammonium polyphosphate, and inorganic nitrogen-containing phosphorus compounds such as phosphamide. Examples of organophosphorus compounds include aliphatic phosphates, phosphoric acid ester compounds, condensed phosphoric acid esters, sulfonic acid compounds, phosphonic acid compounds, phosphine oxide compounds, phosphine compounds, and organic nitrogen-containing phosphorus compounds. series compounds, metal salts of phosphonic acid, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-(2,5-dihydroxyphenyl)-10H-9- Oxa-10-phosphaphenanthrene-10-oxide, 10-(2,7-dihydroxynaphthyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide and other cyclic organophosphorus compounds , phosphorus-containing epoxy resins or phosphorus-containing hardeners, etc., which are derivatives obtained by reacting with compounds such as epoxy resins or phenolic resins.

The compounding amount of the flame retardant is appropriately selected according to the type of the phosphorus-based flame retardant, the components of the epoxy resin composition, and the desired degree of flame retardancy. For example, the phosphorus content in the organic component (excluding the organic solvent) in the epoxy resin composition is preferably 0.2 mass % to 4 mass %, more preferably 0.4 mass % to 3.5 mass %, and more preferably 0.6 mass % Mass % or more and 3 mass % or less. When the phosphorus content is small, it may be difficult to ensure flame retardancy, and when it is too large, it may have a bad influence on heat resistance. Also, when using a phosphorus-based flame retardant, a flame-retardant auxiliary such as magnesium hydroxide may be used in combination.

The epoxy resin composition can be formulated with fillers as needed. Specifically, fused silica, crystalline silica, alumina, silicon nitride, aluminum hydroxide, diaspore, magnesium hydroxide, talc, mica, calcium carbonate, calcium silicate, calcium hydroxide, magnesium carbonate, Barium carbonate, barium sulfate, boron nitride, carbon, carbon fiber, glass fiber, alumina fiber, silica alumina fiber, silicon carbide fiber, polyester fiber, cellulose fiber, aramid fiber, ceramic fiber, microparticle rubber, thermoplastic Elastomers, pigments, etc. Reasons for using fillers include the effect of improving shock resistance. In addition, when metal hydroxides such as aluminum hydroxide, diaspore, and magnesium hydroxide are used, they will function as flame retardant additives and have the effect of improving flame retardancy. The blending amount of these fillers is preferably 1 to 150% by mass, more preferably 10 to 70% by mass, relative to the epoxy resin composition excluding fillers. When the compounding amount is large, there is a possibility that the adhesiveness required for laminate applications may decrease, and the hardened product may become brittle, and sufficient mechanical properties may not be obtained. Also, when the compounding amount is small, there is a possibility that the compounding effect of the filler such as improving the impact resistance of the cured product may not be manifested.

When an epoxy resin composition is used as a plate-shaped substrate or the like, a fibrous one can be cited as a preferable filler in terms of its dimensional stability, bending strength, and the like. More preferably, a fibrous base material in which glass fibers are woven into a mesh shape and a glass fiber substrate using a filler is mentioned.

Various additives such as silane coupling agents, antioxidants, release agents, defoamers, emulsifiers, thixotropic agents, smoothing agents, flame retardants, and pigments can be added to the epoxy resin composition as needed. These additives are preferably in the range of 0.01 to 20% by mass relative to the epoxy resin composition.

By impregnating the fibrous base material with the epoxy resin composition, it can be used as a prepreg used for printed wiring boards and the like. As the fibrous substrate, inorganic fibers such as glass, woven or non-woven fabrics of organic fibers such as polyester resin, polyamine resin, polyacrylic resin, polyimide resin, and aromatic polyamide resin can be used, but are not limited to this. Method of making prepreg from epoxy resin composition The method is not particularly limited. For example, the epoxy resin composition is impregnated in a resin varnish prepared by adjusting the viscosity with a solvent, and then heated and dried to semi-cure the resin component (B stage). For example, it can be obtained at 100 Heat and dry at 200°C for 1 to 40 minutes. Here, the amount of resin in the prepreg is preferably 30 to 80 mass % of the resin content.

When curing the prepreg, a method of curing a laminate generally used in the manufacture of printed wiring boards can be used, but is not limited thereto. For example, when using a prepreg to form a laminate, one or more sheets of prepreg are laminated, metal foil is placed on one or both sides to form a laminate, and the laminate is laminated by heating/pressurizing into one . Here, as the metal foil, single, alloy or composite metal foils of copper, aluminum, brass, nickel, etc. can be used. Furthermore, a laminated board can be obtained by hardening the prepreg by applying heat to the produced laminated product. At this time, it is preferable to properly adjust the heating temperature in the range of 160 to 220° C., the press pressure in the range of 50 to 500 N/cm ² , and the heating and press time in the range of 40 to 240 minutes. Get the desired cured product. When the heating temperature is low, the hardening reaction does not proceed sufficiently, and when the heating temperature is high, the epoxy resin composition may start to decompose. Also, when the applied pressure is low, air bubbles may remain inside the obtained laminate, and the electrical characteristics may be lowered. If the pressure is high, the resin may flow before hardening, and there may be a possibility that a hardened product with the desired thickness may not be obtained. In addition, if the heating and pressing time is short, there may be a possibility that the hardening reaction may not proceed sufficiently, and if it is long, there may be a possibility that the epoxy resin composition in the prepreg may be thermally decomposed.

The epoxy resin composition can be cured by the same method as a known epoxy resin composition to obtain a cured epoxy resin. The method used to obtain the hardened product can be the same method as the known epoxy resin composition, and it is suitable to use casting, injection, filling, dipping, dripping, conveying molding, compression molding, etc., or resin sheet, attached resin Copper foil, prepreg, etc. The form is laminated and heated and pressurized to harden to make a method such as a laminated board. At this time, the curing temperature is usually in the range of 100 to 300° C., and the curing time is usually about 1 to 5 hours.

The epoxy resin cured product of the present invention can take the form of a laminate, a molded product, an adhesive, a coating film, a film, or the like.

The evaluation results of the cured epoxy resin when the epoxy resin composition was prepared and used as a laminate and heat-cured to form a laminate. The cured product can exhibit excellent heat resistance, flame retardancy, and low moisture absorption. It is excellent in adhesiveness, copper foil peel strength and interlayer adhesion strength for printed circuit boards.

(Example)

Although an Example and a comparative example are given and this invention is demonstrated concretely, this invention is not limited to these. Unless otherwise specified, "parts" represent parts by mass, and "%" represent % by mass. In addition, the measurement method was measured by the following method, respectively.

Phenolic hydroxyl equivalent: based on JIS K0070 standard.

Softening point: Measured according to JIS K7234 standard, ring and ball method. Specifically, an automatic softening point device (manufactured by MEITECH Co., Ltd., ASP-MG4) was used.

GPC measurement: used in a body (manufactured by Tosoh Co., Ltd., HLC-8220GPC) equipped with columns (manufactured by Tosoh Co., Ltd., TSKgelG4000H _XL , TSKgelG3000H _XL , TSKgelG2000H _XL ) in series, and the temperature of the column was set at 40°C. In addition, tetrahydrofuran (THF) was used as an eluent, the flow rate was set at 1 mL/min, and a differential refractive index detector was used as a detector. As a measurement sample, 0.1 g of a sample was dissolved in 10 mL of THF and 50 μL was filtered through a microfilter. For data processing, GPC-8020 model II version 6.00 manufactured by Tosoh Co., Ltd. was used. The n=0 component amount was calculated from the obtained chromatogram, and the amount of n=0 was calculated by standard monodisperse polystyrene (manufactured by Tosoh Co., Ltd., A-500, A-1000, A-2500, A-5000, F-1 , F-2, F-4, F-10, F-20, F-40, F-80, F-128) to determine the number average molecular weight (Mn), weight average molecular weight (Mw), Dispersion (Mw/Mn).

Glass transition temperature (Tg.DSC): based on IPC-TM-650 2.4.25.c, by means of a differential scanning calorimetry device (manufactured by Hitachi High-Tech Science Co., Ltd., EXSTAR6000 DSC6200) at 20°C/min DSC when measuring at elevated temperature. Tgm (intermediate temperature of the variation curve relative to the junction of the glass state and the rubber state) is expressed in temperature.

Glass transition point (Tg.TMA): Tg was obtained with a thermomechanical measurement device (EXSTAR6000TMA/6100 manufactured by SII NanoTechnology Co., Ltd.) at a temperature increase rate of 10°C/min.

Flame retardancy: evaluated by vertical method according to UL94. The evaluations are described as V-0, V-1, and V-2. But the complete burner is recorded as x.

Copper foil peeling strength and interlayer adhesion: Measured according to JIS C6481 standard, interlayer adhesion is measured by peeling between the seventh layer and the eighth layer.

Water absorption: According to JIS K7209 standard. The test piece was measured by immersing in water at 23° C. for 24 hours using the sample used in the measurement of dielectric constant and dielectric loss tangent.

Specific permittivity and dielectric loss tangent: According to IPC-TM-650 2.5.5.9, use a material analysis device (manufactured by AGILENT Technologies Co., Ltd.) to obtain the specific permittivity and dielectric loss tangent at a frequency of 1 GHz by the volumetric method.

[epoxy resin]

(A-1): Phosphorus-containing epoxy resin (manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., product name: FX-1225, epoxy equivalent 320, phosphorus content 2.5%)

(A-2): Phosphorus-containing epoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., product name: YDFR-1320, epoxy equivalent 747, phosphorus content 5.0%)

(A-3): Dicyclopentadiene-type epoxy resin (manufactured by DIC Corporation, product name: HP-7200H, epoxy equivalent 280, softening point 82° C.)

(A-4): Biphenol aralkyl type epoxy resin (resin synthesized according to the method described in Synthesis Example 1 of Patent Document 6, epoxy equivalent 197, melting point 125°C)

[hardener]

(B-1): The biphenyl aralkyl type phenolic resin obtained in Synthesis Example 1

(B-2): The biphenyl aralkyl type phenolic resin obtained in Synthesis Example 2

(B-3): The biphenyl aralkyl type phenolic resin obtained in Synthesis Example 3

(B-4): The biphenyl aralkyl type phenolic resin obtained in Synthesis Example 4

(B-5): The biphenyl aralkyl type phenolic resin obtained in Synthesis Example 5

(B-6): The biphenyl aralkyl type phenolic resin obtained in Synthesis Example 6

(B-7): The biphenyl aralkyl type phenolic resin obtained in Synthesis Example 7

(B-8): Phosphorus-containing phenol hardener (manufactured by Shin-AT&C, product name: LC-950PM60, phenolic hydroxyl equivalent 340, phosphorus content 9.2%)

(B-9): Phenolic novolak resin (manufactured by Aica SDK Phenol Co., Ltd., product name: BRG-557, phenolic hydroxyl equivalent 105)

(B-10): Phenolic resin (manufactured by Meiwa Chemical Co., Ltd., product name: MEH-7851-3H, phenolic hydroxyl equivalent 223)

(B-11): Phenolic resin (manufactured by Qunrong Chemical Industry Co., Ltd., product name: TPM-100, phenolic hydroxyl equivalent 98)

(B-12): Dicyandiamide (manufactured by Japan Carbide Industry Co., Ltd., product name: DIHARD, active hydrogen equivalent 21)

[hardening accelerator]

(C-1): 2-Ethyl-4-methylimidazole (manufactured by Shikoku Chemical Industry Co., Ltd., product name: Curezol 2E4MZ)

(C-2): Triphenylphosphine: (manufactured by Hokko Chemical Co., Ltd., product name; Hokko TPP)

Synthesis Example 1

Add 246.2 parts (1.32 moles) of 4,4'-biphenol, 379.1 parts of diethylene glycol dimethyl ether, and 4,4'-dichloromethane to a reaction device equipped with a stirrer, a thermometer, a nitrogen blowing tube, and a cooling tube 132.9 parts (0.53 moles) of base biphenyl were heated up to 170°C while stirring under a nitrogen stream, and the reaction was carried out for 2 hours. After the reaction, the whole amount of diethylene glycol dimethyl ether was distilled off under reduced pressure, 311 parts of toluene and 104 parts of methyl isobutyl ketone were added and stirred and mixed, and after cooling to room temperature, the precipitated n=0 component After filtering off, toluene and methyl isobutyl ketone were distilled off, and 187 parts of biphenyl aralkyl type phenol resins (B-1) were obtained. The physical properties of the obtained resin are shown in Table 1, and the GPC is shown in Fig. 1 .

Synthesis example 2

After the reaction was performed in the same manner as in Synthesis Example 1, the entire amount of diethylene glycol dimethyl ether was distilled off under reduced pressure, 473 parts of toluene and 158 parts of methyl isobutyl ketone were added and mixed with stirring, and cooled to room temperature Then, after filtering off the precipitated n=0 component, toluene and methyl isobutyl ketone were distilled off, and 203 parts of biphenyl aralkyl type resins (B-2) were obtained. The physical properties of the obtained resin are shown in Table 1, and the GPC is shown in Fig. 2 .

Synthesis example 3

After the reaction was carried out in the same manner as in Synthesis Example 1, 379 parts of toluene was added and mixed with stirring. After cooling to room temperature, the precipitated n=0 component was filtered off, diethylene glycol dimethyl ether and toluene were distilled 153 parts of biphenyl aralkyl type phenol resins (B-3) were obtained. The physical properties of the obtained resin are shown in Table 1, and the GPC is shown in Fig. 3 .

Synthesis Example 4

Add 269.9 parts (1.45 moles) of 4,4'-biphenol, 379.1 parts of diethylene glycol dimethyl ether, 109.2 parts (0.44 mol), and the temperature was raised to 170° C. while stirring under a nitrogen flow, and the reaction was carried out for 2 hours. After the reaction, the whole amount of diethylene glycol dimethyl ether was distilled off under reduced pressure, 260 parts of toluene and 87 parts of methyl isobutyl ketone were added and stirred and mixed. After cooling to room temperature, the precipitated n=0 After components were filtered off, toluene and methyl isobutyl ketone were distilled off to obtain 190 parts of biphenyl aralkyl type phenol resins (B-4). The physical properties of the obtained resin are shown in Table 1, and the GPC is shown in Fig. 4 .

Synthesis Example 5

Add 226.4 parts (1.22 moles) of 4,4'-biphenol, 379.1 parts of diethylene glycol dimethyl ether, 152.7 parts (0.61 mol), and the temperature was raised to 170° C. while stirring under a nitrogen flow, and the reaction was carried out for 2 hours. After the reaction, the whole amount of diethylene glycol dimethyl ether was distilled off under reduced pressure, 250 parts of toluene and 83 parts of methyl isobutyl ketone were added and stirred and mixed. After cooling to room temperature, the precipitated n=0 After the component was filtered off, toluene and methyl isobutyl ketone were distilled off to obtain 183 parts of biphenyl aralkyl type phenol resin (B-5). The physical properties of the obtained resin are shown in Table 1, and the GPC is shown in Fig. 5 .

Synthesis Example 6

After the reaction was carried out in the same manner as in Synthesis Example 1, the entire amount of diethylene glycol dimethyl ether was distilled off under reduced pressure, 424 parts of toluene and 85 parts of methyl isobutyl ketone were added and mixed with stirring, and cooled to room temperature Then, after filtering off the precipitated n=0 component, toluene and methyl isobutyl ketone were distilled off, and 158 parts of biphenyl aralkyl type phenol resins (B-6) were obtained. The physical properties of the obtained resin are shown in Table 1, and the GPC is shown in Fig. 6 .

Synthesis Example 7

After the reaction was carried out in the same manner as in Synthesis Example 1, the entire amount of diethylene glycol dimethyl ether was distilled off under reduced pressure, 339 parts of methyl ethyl ketone was added and stirred and mixed, and after cooling to room temperature, the precipitated After filtering off the n=0 component, methyl ethyl ketone was distilled off to obtain 208 parts of biphenyl aralkyl type phenol resin (B-7). The physical properties of the obtained resin are shown in Table 1, and the GPC is shown in Fig. 7 .

Example 1

A resin composition was obtained by kneading 100 parts of (A-4) as an epoxy resin, 80 parts of (B-1) as a curing agent, and 1 part of (C-2) as a curing accelerator. Use the obtained epoxy resin composition in Molding was performed at 175°C, followed by post-curing at 175°C for 12 hours to obtain a cured product. Table 2 shows the glass transition temperature (Tg.TMA) of the cured product.

Examples 2 to 4 and Comparative Examples 1 to 4

In addition to using the resins (B-3) to (B-7) obtained in Synthesis Examples 3 to 7, or the phenolic novolac resin (B-9), and the phenolic resin (B-11), and setting it as the formulation of Table 2, For the rest, an epoxy resin composition was obtained in the same manner as in Example 1, and a cured product was obtained. Table 2 shows the results of the same test as in Example 1. In addition, "-" in the table indicates that it is not used.

Example 5

Prepare 100 parts of (A-1) as a phosphorus-containing epoxy resin, 50 parts of (B-1) as a hardener, and 0.03 parts of (C-1) as a hardening accelerator, dissolve in MEK, propylene glycol mono A mixed solvent adjusted with methyl ether and N,N-dimethylformamide to obtain an epoxy resin composition varnish. The resulting epoxy resin composition varnish was impregnated with glass cloth (manufactured by Nitto Bosho Co., Ltd., WEA 7628 XS13, 0.18mm thick). The impregnated glass cloth was dried in a hot air circulating oven at 150° C. for 9 minutes to obtain a prepreg. 8 sheets of the obtained prepreg were overlapped with copper foil (manufactured by Mitsui Metal Mining Co., Ltd., 3EC-III, thickness 35 μm) from top to bottom, and were subjected to 2MPa under the temperature conditions of 130°C x 15 minutes + 190°C x 80 minutes. Vacuum extrusion to obtain a 1.6mm thick laminate. The copper foil portion of the obtained laminate was removed by immersing in an etchant, washed and dried, and then cut out to a size of 127 mm×12.7 mm as a test piece for flame retardancy measurement. Table 3 shows the results of copper foil peel strength, interlayer adhesion, glass transition temperature (Tg.DSC) and flame retardancy of the laminate.

Further, the obtained prepreg was loosened and sieved to form a powdery prepreg powder passing through 100 meshes. The obtained prepreg powder was placed in a mold made of fluororesin, and subjected to vacuum extrusion at 2 MPa under the temperature conditions of 130°C x 15 minutes + 190°C x 80 minutes to obtain a test piece of 50 mm square x 2 mm thick. Table 3 shows the results of water absorption, specific permittivity, and dielectric loss tangent of the test pieces.

Examples 6 to 8 and Comparative Examples 5 to 8

(A-1) as epoxy resin, (B-1) to (B-2) as hardener, (B-4) to (B-5), (B-9) to (B-12 ), (C-1) as a hardening accelerator was formulated according to the formulation amount (parts) in Table 3, and the same operation as in Example 5 was carried out to obtain a laminate and a test piece. The same test as in Example 5 was performed, and the results are shown in Table 3.

Examples 9 to 12 and Comparative Examples 9 to 12

(A-1) to (A-3) as epoxy resin, (B-1) as hardener, (B-8) to (B-9) as hardening accelerator (C-1) According to the compounding amount (parts) in Table 4, the same operation as in Example 5 was carried out to obtain a laminate and a test piece. The same test as in Example 5 was performed, and the results are shown in Table 4.

From these results, it can be seen that the epoxy resin composition using the biphenyl aralkyl type phenolic resin has high heat resistance, and exhibits sufficient performance in low water absorption and adhesiveness. Especially when phosphorus-containing epoxy resin is used, an epoxy resin composition with higher flame retardancy can be obtained.

Claims (7)

An epoxy resin composition, which uses epoxy resin and a hardener as essential components, wherein more than 50% by mass of the hardener and less than 100% by mass are biphenyl aralkyl groups represented by the following general formula (1) Type phenol resin, the phenolic hydroxyl equivalent of this biphenyl aralkyl type phenol resin is 150 to 180g/eq., and in the gel permeation chromatography measurement, n is the composition of 0 in the general formula (1) does not reach 15 area%, n is 5 or more components are 20 area% or more,

Here, n is the number of repeating units and represents a number of 0 or more, and its average value is a number of 1.3 to 20, and R ¹ , R ² and R ³ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms. The epoxy resin composition as described in claim 1, wherein a part or all of the above-mentioned epoxy resin is a phosphorus-containing epoxy resin. A hardened product, which is obtained by hardening the epoxy resin composition described in item 1 or 2 of the scope of application. A prepreg obtained by using the epoxy resin composition described in item 1 or 2 of the patent application. A laminate obtained by using the epoxy resin composition described in item 1 or 2 of the patent application. A printed circuit board obtained by using the epoxy resin composition described in item 1 or 2 of the scope of application. A kind of curing agent for epoxy resin, is to comprise the biphenyl aralkyl type phenol resin shown in following general formula (1), the phenolic hydroxyl equivalent of this biphenyl aralkyl type phenol resin is 150 to 180g/ eq., and in the gel permeation chromatography measurement, in the general formula (1), the component where n is 0 is less than 15 area %, and the component where n is 5 or more is 20 area % or more,

Here, n is the number of repeating units and represents a number of 0 or more, and its average value is a number of 1.3 to 20, and R ¹ , R ² and R ³ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms.

Images